Piano



(No Model.)

` C. GHATPIELD.

PIANO No. 464,553. Patented Deo. 8, 1891.

To @ZZ whom it may concern,.-

ybraces being provided at one end with gradu- UNITED STATES PATENT OFFICE.

CHARLES OIIATFIELD, OF MALDEN, MASSACHUSETTS.

PIANO.

SPECIFICATION forming part of Letters Patent No. 464,553, dated December 8, 1891.

Application filed August 24, 1891.

Be it known that I, CHARLES CHATFIELD, of Malden, in the county of Middlesex, State of Massachusetts, have inventedcertain new and useful Improvements in Pianos, of which the followi-ng is a description suiciently full, clear, and exact to enable any person skilled in the art or science to which said invention appertains to make and use the same, reference being had to the4 accompanying drawings, forming part of this specification, in which- Figure 1 is a perspective view showing the string and sounding-board frame of my improved piano, and Fig. 2 alike view of the sounding-board detached.

Like letters and figures of reference indicate corresponding parts in the different figures of the drawings.

My invention relates especially to sounding-boards for upright pianos; and it consists in certain novel features hereinafter fully set forth and claimed, the object being to produce a simpler, cheaper, and more effective device of this character than is now in ordinary use.

The nature and operation of the improvement will be readily understood by all conversant with such matters from the following explanation.

In the drawings, A represents the frame considered as a whole, and D the soundingboard. The frame consists, primarily, of the wrest-plank b and base or string-key plank d, connected at their ends by braces f. Parallel back braces g also connect said planks, said ated projections or cleats 7L, against which the wrest-plank bears, the purpose of said cleats being to resist the strain of the strings on said plank. At one end above a brace f a triangular brace z' connects said planks b d, its base or broad end bearing against the keyplank d. Above the opposite brace f the planks are connected by a brace j, said brace near the wrest-plank having a lateral projection 7c. Near the triangular brace i the wrest and key planks are respectively provided with vertical sockets m p. The projection k of the brace 7' has a similar socket q and the keyplank a corresponding socketrnear said brace.

The sounding-board D is double, it being` constructed on the principle of a violin-body and consisting of a box quadrilateral in plan View, formed from an upper board 15 and lower board 16, connected by side pieces 17 and end pieces 1S. The end pieces 18 are extended beyond the sides 17. A metallic arch or truss 2O is secured to each side piece with its ends bearing against the overlapping ends of the end pieces 18, said trusses serving to brace the board and prevent the pressure of the strings from binding or sagging it. On each end piece 1S a similar metallic brace 21 is secu red, the ends thereof projecting slightly below the end pieces 1S in position to bear against the wrest and key planks when the sounding-board is adjusted in the frame. These trusses brace the board against being bent longitudinally by the pressure of the springs. The upper board 15 is provided with a sound-opening 25, and two curved stringbridges 26 and 27 are mounted thereon. The position of the hole and bridges may be varied as desired. Then mounted inthe frame, the projecting ends of the end pieces 18 of the board D arc inserted in the sockets m p q r, respectively, and form the only bearingpoints of the board in the frame. The cleats h, braces g j i, and base-plank d are so arranged that they do not come into contact with the sounding-board. By mounting the sounding-board in the frame in this' manner its vibration is not interfered with and the volume of sound is greatly intensiiied. Moreq over, the device constructed as described is exceedingly durable and little liable to become displaced or distorted by the action of temperature on the Wood.

Having thus explained my invention, what I claim is 1. In a piano, a double sounding-board constructed of a top and bottom board connected by side and end pieces, the ends of corresponding pieces being projected beyond the board to enter sockets in the frame, whereby it is supported, substantially as described.

2. A sounding-board for pianos, comprising a box having corresponding side pieces elongated, substantially as and for the purpose set forth. H

3. A sounding-board for pianos, comprising a box provided in one face with a sound-open- IOO . forth.

5. The sounding-boardD, provided with the elongated sides 1S and trusses 2O and 2l, substantially as and for the purpose set forth.

G. The sounding-board D, provided with the elongated sides ltrusses 20 and 2l, opening 25, and bridges 26, arranged to operate substantially as set forth.

7. In apiano, a sounding-board comprising a hollow quadrangular box having elongated side pieces, in combination with a frame coniprising a Wrest-plank, key-plank, and connect-- ing-braces and provided with sockets for receiving the ends ot' said side pieces, substantially as set forth.

S. In a piano, the frame A, comprising the planks b d, connected by braces, as f g t' j, and provided with sockets, as m p q r, for receiving the corners of a sounding-board, substantially as set forth.

9. In a piano, the frame A, comprising thc planks b d, connected by braces f g j and triangular brace i, and provided with the projections or cleats 7l, secured to said braces g, substantially as and for the purpose set forth.

CHARLES CHATFIELD.

Vitnesses:

O. M. SHAW, F. S. DUNNING. 

